Heidi Klum and SealHeidi Klum and SealIt's official - dressing up is the new dressing down.

So say the hosts of celebrities who are donning increasingly daring outfits in the name of fun.

It's a trend that has been set by icons such as Elton John, Vivienne Westwood and Jonathan Ross, who are all famed for wearing natty outfits in public.

Half-hearted efforts just won't do. The more extravagant the better.

Heidi Klum and her fiance Seal have become notorious for it - Heidi hosts a lavish Halloween party each year, for her band of loyal dresser-uppers who hire expensive gowns for the day.

Other famous faces often seen in headline-grabbing garb include rapper P Diddy, Moby, Eminem and Alan Titchmarsh.

Visit our picture gallery to see them.